Cylinder lubrication.



J. C. COOK & C. B. WELEVER.

CYLINDER LUBRIGATION.

APPLICATION FILED MAR. 18, 1911.

Patented Feb. 18, 1913.

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UNITED STATES PATENT OFFICE.

JAY C. COOK AND CLARENCE E. WELEVER, 0F PASADENA, CALIFORNIA.

CYLINDER LUBRICATION.

Specification of Letters Patent.

Application filed March 18, 1911.

Patented Feb. 18,1913. Serial No. 615,482.

To all whom it may concern:

Be it known that we, JAY C. COOK and CLARENCE E. lVELEvER, both citizensof the United States, residing at Pasadena, in the county of Los Angelesand 'State of California, have invented new and useful Improvements inCylinder Lubrication, of which the following is a specification.

This invention relates to the lubrication of cylinders and pistons ofinternal combustion engine's, especially to that type wherein what isknown as the splash system of lubrication is employed. In such systemsof lubrication considerable difficulty is experienced by oil workingabove the piston and causing carbon to collect on the piston and valves,necessitating frequent regrinding of the valves and cleaning of thespark plugs. This deposit of carbon invariably results when too much oilis placed in the crank base. To avoid this it is custommy to limit theamount of oil placed in the crank base and this requires, in many typesof engines, the frequent replenishing of the oil, and the main object ofthe present invention is to prevent the oil from working above thepiston and thereby avoid the fori mation of carbon referred to, thuseliminating all of the evils arising therefrom, such as loss of power,valve trouble, ignition trouble, etc., and to also enable a much largersupply of oil to be carried.

Our invention consists in providing one or more holes through the wallsof the piston leading from a piston ring groove to the space in theinterior of the piston which is in direct communication with the crankbase, which permits any excessive oil which has worked up the walls ofthe cylinder and piston to pass inwardly through the holes and falltherefrom directly into the supply of oil in the crank base, thepresence of the holes making it impossible for the excessive oil to passabove them.

Referring to the drawings :Figure' 1 is a vertical section through aportion of an internal combustion engine, showing it constructed inaccordance with our invention. Fig. 2 is a cross section on line w wFig. 1.

1 designates a cylinder.

2 designates the crank base with oil sup- 4 designates the piston havingpiston rings 5 at the upper end thereof.

.7 designates holes drilled through the wall of the piston andcommunicating with the around the inner faces of the piston ringsas thepiston rings are expanded and fit tight against the cylinder walls, sothat any excessive oil which reaches the lower piston ring 6 willarrive'at the bottom of the groove in which that piston ring lies andwill thus flow out through the holes 7 and drop back into the oilreservoir. This prevents any excess oil Working above this point andprevents the formation of carbon before referred to.

In nearly all modern engines the internal diameter of the cylindersvaries, the diameter being from three to seven thousandths of an inchless at the upper end of the stroke than atthe lower end of the stroke,so that as the piston rises during compression the piston rings arecontracted from three to seven thousandths of an'inch, which gives thema tighter fit at the point where it is most needed for good compression.As the piston descends the rings expand gradually so that as the pistonreciprocates there is a slight expansion and contraction of the pistonrings which acts after the manner of a pump to force the oil from thepiston ring groove through the perforations. Thus as the. pistondescends the ring expands and the oil, working around the inner face ofthe ring lodges, in the groove in the pistonbehind the piston ring, andas the piston ascends the oil which has accumulated in this groove atthe back of the ring is forced through the perforations by the pistonring as the latter is contracted and forced deeper into the groove.

Having provided means for returning an excess of oil after it hasreached a given height, it. is possible to increase the amount carriedin the reservoir and thereby increase the oil capacity of' the machinewithout causing any disadvantageous results. The perforations 7 beinglocated at a point above the wrist pin 8 results in causing the wristpin to be lubricated by the oil which passes out through theperforations 7.

What we claim is A crank case, a cylinder thereon, a trunk piston in thecylinder, the piston having an annular groove and formed withperforations which extend from the inner wall of said groove to the openspace within the piston, said space having direct communication in thepiston and discharged to the crank with the crank case, and animperforate split case.

expansible piston ring in said groove where- In testimony whereof, Wehave hereunto by the expansion and contraction of the pis- E set ourhands at Los Angeles California this 5 ton ring during the stroke of thepiston 28 day of February 1911.

causes'the oil which Works into said groove JAY C. COOK.

to be pumped by the radial movement of the CLARENCE E. WELEVER. pistonring caused by its expansion and con- Witnesses:

traction during the stroke of the piston G. T. HACKLEY,

10 through the perforations into the space with- FRANK L. A. GRAHAM.

